Conclusion

If the library was brought to Qumran, as seems likely, given the variety of scribal hands and the number of documents, there is little doubt that it came from Jerusalem. Jerusalem was obviously the place, a day's walk from Qumran, where a library of this magnitude would be maintained. The most likely date when the scrolls may have been taken to the caves for safekeeping is sometime after 66 A.D., when Jerusalem was threatened by the First Jewish Revolt against Rome.
Norman Golb of the University of Chicago argues that the scrolls were in fact the Temple library. But the documents themselves fairly refute this idea. There is not a single Pharisaic or Sadducean document in the collection, and these were the two most prominanent groups controlling the Temple hierarchy during the period of the scrolls. Indeed, the scrolls express frequent opposition to the Jerusalem Temple.
Some authors believe that the library belonged to another group, perhaps the Essenes of Jerusalem (who lived near the Essene Gate)-or perhaps some other group whom we cannot identify.
That there are other possibilities canot be denied. But none carries much conviction. We are left with mere specualtion. Anyone can play the game. The uncertainties will remain-until perhaps new evidence surfaces.